Index: extobj.h
===================================================================
--- extobj.h	(revision 11159)
+++ extobj.h	(revision 11160)
@@ -47,6 +47,10 @@
 RND_INLINE void csch_extrobj_attr_edit_pre(csch_cgrp_t *grp, const char *key);
 RND_INLINE void csch_extrobj_attr_edit_post(csch_cgrp_t *grp, const char *key);
 
+/* Invoke the extobj-specific GUI dialog for editing object properties, if
+   present. Returns 0 on success (dialog invoked). */
+RND_INLINE int csch_extobj_gui_edit_dlg(csch_cgrp_t *grp);
+
 /*** for implementing extended objects ***/
 
 /* return the extobj-gfx group within grp or NULL if not found */
@@ -81,3 +85,13 @@
 		grp->extobj->attr_edit_post(grp, key);
 }
 
+RND_INLINE int csch_extobj_gui_edit_dlg(csch_cgrp_t *grp)
+{
+	if ((grp->extobj_inhibit == 0) && (grp->extobj != NULL) && (grp->extobj->gui_edit_dlg != NULL)) {
+		grp->extobj->gui_edit_dlg(grp);
+		return 0;
+	}
+
+	return 1;
+}
+